Manufacture of strip rubber



C. W. LEGUILLON MANUFACTURE oF STRIP RUBBER Dec. 8, `1942.

Filed April 50, 1957 .Patented Dee. 8,1942 n Y rtnuxmmo'run,E oF STRIP RUBBER vCharles W. Leguillon, Akron, Ohio, assignor tdf- The B. F. Goodrich Company, New York, N. Y., a corporation of New York Application April 30, 1937, Serial No. 13.9,88`3

Claims.

This invention relatesv to the manufacture of strip rubber such, for example, as the elastic Y thread used in elastic garments.

The principal lobjects of the ivention are to provide improved rubber thread, to provide procedure and apparatus for making strip material conveniently, economically and of uniform high quality, to control the shape Vand dimensions of the strip'and to provide for the continuous production of a strip of great length.

YThese and other objects will appear from the following description and the accompanying drawing.

Of the drawing:

Fig.'1 is a side elevation of the apparatus of the invention with parts broken away and parts shown in section. I Y

Fig. 2 is a sectional detail view taken on line 2 2 of Fig. 1 and showing the masking wheel in one of its forms as immersed in the dispersion, parts being broken away. Y

Fig. 3 is a 'perspective view of a lnishedrub'- ber strip resulting from the use of an anode of cirqilar cross-section with'the masking wheel of Fig. 2\

Fig. 4 is an axial cross-sectional view of'v another 'form of masking wheelY and anode as used in the production of square thread.

drives a sprocket wheel 22"-mounted on `a shaft v 22a, by means of a chain l23.

Fig. 5 is a perspective view of the thread produced by the use kof a flat wire anode and the masking wheel of Fig. 4.

Referring'to the drawing, the invention con-` templates the progressive deposit of rubber from a natural or artificial dispersion thereof upon a travelling flexible anode preferably in the form of a wire of any desired cross section while masking the anode or form about a portion ofits surface to prevent deposit thereon except "upon thev desired part of the .anode surface. The anode IIJ may be coiled about a drum II and is delivered therefrom to the face of `a masking wheel I2 which is mounted to rotate freely about its axis with a yportion of its perimeter immersed in a bath |3 of latex or other natural or articial aqueous dispersion of rubber. After leaving the masking'wheel the anode or flexible form is conducted about guide pulleys I4 and I5 and is rewound about a drum I6. f

For advancing the form or anode through the dispersion from drum to drum I6, an electric motor I'l is provided which drives the drum I6 by means such as a worm I8, a worm wheel I9 driven thereby, and a sprocket 2|) mounted on a Shaft 22a also' carriesV a Vsprocket 24, fixed thereto, which drives a sprocket 25 fixed to drum I6 by a chain 26. f

The bath which holds the dispersion comprises a tankl 21 within which is suspended a smaller.

tank 28. An electric motor 29 carries an im peller blade 30 which is immersed in the .dis-

persion between the two tanks and functions to circulate the dispersion, causing it to rise locally in the outer tank and flow into the innertank which in turn overflows as at |3a into the outer tank.Y The arrangement is such that the inner tank is keptr at constant level. y

In order to mask the anode or form as it passes through the dispersion, the masking wheel I2 is provided with a rim 3| of insulating material such'A as soft vulcanized rubber or other material having substantially the Yphysical properties thereof, semi-hard rubberhard rubber, Bakelite, or Vother insulating material formed with a groove 32 having Va width equal to or slightly less than the width of the anode wire. When an anode of circular cross section is used, as shown in Fig. 2, the

bottom of the groove may be V-shaped whereas when an anode ofvribbon form isused as illustrated in Fig. 4, the groove may be ilat bottomed. Where the rim 3| is made ofv resilient material, such as soft rubber, semi-hard rubber, or rubber like material, such as polymerized vinyl chloride, the resilience of the material maybe utilized to effect a sealing pressurebetween the sides of the groove and the flexible form and the slot 32 mayv be made slightly less in width than the form for .this purpose, although deposit entirely around Y shaft 2| to which worm wheel' I9 is xed, which 55 the form willordinarily be prevented'by the close contact between the bottom of the groove and the form caused by the driving tension on the form. Where harder materials such as hard rubber or Bakelite are used for forming the rim 3|, the slot should be accurately formed to the same Width" as the flexible form unless it is desired to have thev form ride on the outer margins of the rim defining the groove and to depend upon tensioning of the form to seal off a portion of its surfa'ce.

Where a exible wire is used as the form, aV cathode 33 may be limmersed inthe tank 28 and f s is connected to a negative electrical source andY .a brush 34 or other contacter, connected to a positive source, is mounted to bear against the wire `III as it leaves the drum |I, whereby to charge the wire positively and cause rubber from the dispersion to deposit thereon.

As the rim 3| of the masking wheel is Vof inv thereagainst,

The leading end of the deposited strip 35 is led over a belt 31 and is progressively stripped from the Ywire by the pull of the belt. Belt 31 may be driven at the same velocity as the anode wire, or at a slightly greater velocity if desired, and for this purpose suitable driving means may be provided such as a sprocket 39 xed to shaftl 22a adapted to drive a sprocket fixed to a shaft 39, through a chain 49, a sprocket 4Ixed to shaft 49, a sprocket 42 iixed to shaft 43, about which the belt 31 is driven by a pulley 44, and a. chain 45.

Shaft 39 is rotatably mounted on one end of an oven 46, and a shaft 41 is similarly mounted at the opposite end of the oven.Y A conveyor belt 48 is driven by shaft 39 and functions to carry the rubber'strip through the oven where the strip may be dried or vulcanized as desired.

As the dried or vulcanized .strip leaves thf` oven it may be wound on a spool 49. The spool 49 may be driven by contact with a pair of cradle rolls 50, on which it rests, one of these rolls being driven by a belt 52 from a pulley1 53 fixed to shaft 41.

AIn practicing the inventionV the electrically charged wire I0 is drawn from the drum Il unlder slight braking tension and is passed through a natural or articial dispersion of rubber at such aV velocity as to cause deposit of rubber thereon to the desired thickness. The wire is masked by the wheel l2 so that only the desired lportion of its surface is exposed Ato receive the deposit. Deposit on the wheel I2 is prevented by the insulating material of which its rim is comprised. The deposited strip is removed from the wire and dried or vulcanized as desired. By using wires of different shapes and dimensions and masking wheels adapted thereto,

the size' and cross sectional shape of the rubber r strip may be controlled nicely. When asquare or fiat wire is used in the rectangular groove,

the resulting strip will be rectangular /as il1us/ trated in Fig. 5. Where a round wire is used the resulting strip will be concave on one face and convex on the opposite face andwhen made in the parallel-sided groove it will Vhave its remaining sides parallel, L

By. use of this method a rubber thread of extreme length may be accurately produced. While ordinarily the length of the rubber thread is limited by the length of the anode Wire, by using an endless wire belt, a thread of any desired length may be produced.

While I prefer to employ the electro-deposition process for selectively securing a deposit upon the flexible wire or other traveling form, other known methods of securing ra selective deposit may be used in forming the strip of` ru ber. For instance by eliminating the cathode 33 and passing a current along the .wire of ksufilcient strength to heat the Wire, or by other- Y 2,301,577 Y L wise heating the wire as it enters thebath, and employing a dispersion sensitive to heat, selective deposit of'rubber upon the Wire may be attained. Furthermore by coating the wire or other flexible form with a coagulantchemical as by a swab 54 before the wire .ispassed into the dispersion, such coagulant will cause selective deposit upon thewire and the electric current may be dispensed'with.

I claim:

groove-walls of a circumferentially grooved wheel, and electro-depositing a coating upon the exposed surface of the wire.

2. Apparatus for making a strip of rubberlike material, said apparatus comprising a bath of liquid-dispersed rubber,V afwheel having a grooved rim of insulating material partially immersed therein, means for progressively passing a conductive strip former about the wheel within a groovethereof through said bath, means for electrically charging the strip former to effect for electro-deposit of a coating of rubber upon the exposed surface of said former, and means :for progressively removing .the coating from the former. l

3. Apparatus for making a strip of rubberlike material, said apparatus comprising a bath of dispersed rubber-like material, a grooved wheel partially immersed therein, means for progressively passing an extensive flexible former about the wheel in the groove thereof through said bath, means for selectively depositing a coating of rubber-like material upon the exposedsurface of -said former, and meanson said wheel for resiliently contacting the sides of the former and protecting portions of the former from Vdeposits of coating thereon.

4. Apparatus for making a strip of like material, said apparatus comprising a bath of dispersed rubber, a wheel partially immersed therein and having its rim formed of resilent insulating material, said rim having a circum- ,Wire to a bath of dispersed rubber-like material to provide a' coating of said material thereon, a wheel having a peripheral groove adapted to engage the wire Yas it approaches the bath with the sides of the groove in sealed engagement with the wire to prevent Contact of the material with a longitudinal zone of the Wire while gulding the wire through the bath of material to prevent deposit therealong, means for releasing the strip from said Wire as the wire leaves the bath of material, and means for effecting deposit of the material upon the surface of the wire exposed to the bath.

CHARLES W. LEGUILLON.

1. The method of making a strip of rubberrubber- 

